Variable-camber cylinder



Dec. 28, 1965 P. J. FARA VARIABLE-CAMBER CYLINDER Filed April 1, 1964 w .mw .N MNNN United States Patent O f 3,225,418 VARIABLE-CAMBER CYLINDER Pierre Jacques Fara, Viilemomble, France, assigner to DLM. Nanterre, Seine, France, a company of France Filed Apr. 1, 1964, Ser. No. 356,440 Claims priority, application France, Apr. 8, 1963, 930,763, Patent 1,365,334 6 Claims. (Cl. 29--113) The present 'invention relates to a variable-camber cylinder of the type comprising a bushing mounted on anti-friction bearings which rest on a shaft and means for imparting to said shaft curvatures which are transmitted to the bushing by the antifriction bearings.

Cylinders of this type are already known which are put to use by giving them a certain camber and which are thus capable, for example, of either widening or narrowing a continuous strip in a machine designed for the purpose of processing products which are fabricated in the form of strips or alternatively of spacing apart juxtaposed strips which have just been cut out longitudinally from a single band.

Cylinders of the same type are also employed in machines in which any .axially extending line on the periphery of the cylinder must be maintained perfectly straight during the processing operation, said cylinder being accordingly prestressed when in the inoperative state by bending the cylinder shaft so as to produce a longitudinal curvature which is cancelled during operation as a result of the force which is applied on the cylinder.

In one case as in the other, the cylinders which have been employed until the present time have proved both complex in design and unreliable in operation. In addition, such cylinders have called for the utilization of substantial forces in order to obtain the requisite camber and have therefore made it difficult to produce said camber by automatic control, which is a desirable feature.

The object of the present invention is to overcome the disadvantages noted Iabove and is accordingly directed to a cylinder of the type referred to above which is characterized in that the means for imparting to the cylinder shaft the curvatures which are transmitted to the bushing by the lantifriction bearings consist of rings having spherical faces which are alternately male and female and which are alternately fitted with play and without play around the cylinder shaft, provision being made for a device which is operated from the exterior and which can displace off-center the rings which are fitted with play around said cylinder shaft.

It will be readily understood that, when the device for shifting off-center the rings which are fitted with play over the cylinder shaft is put into operation, the other rings are accordingly moved away from each other on one radial side of the shaft and are moved closer together on the opposite radial side of the shaft with the result that said rings perform a movement of rotation .about their central point which is located on the geometrical axis of the system. The different movements of rotation of the various rings which are fitted without play over the cylinder shaft cause this latter to assume a camber or curvature which is directly dependent on the amount of off center displacement of the rings which are fitted with play over the cylinder shaft.

In a preferred embodiment, of the invention the device for displacing off-center the rings which are fitted with play over the cylinder shaft -consists of a liner tube which extends within the interior of the shaft which is hollow, said liner tube being expandable for the purpose of moving ribs which are placed within holes pierced through the hollow shaft, said ribs being interposed between the liner tube and the rings which are tted with play.

3,225,418 Patented Dec. 28, 1965 ICC As a preferable feature, the liner tube is hollow and filled with water and the expansion thereof is produced by axial compression exerted by a screw which moves axially with respect to one end of the cylinder shaft.

As will be apparent, it is thus possible merely by tightening or slackening-off the screw to produce the radial expansion or contraction of the liner tube and therefore the displacement off-center of the rings which are fitted on the shaft with play, thereby producing the requisite camber of the cylinder.

As an advantageous feature, the rings which lare fitted with play are male rings and the female rings are made integral with the antifriction bearings. The female rings can accordingly be in the form of rings which are secured on opposite sides of each antifriction bearing, except of Course at the ends where provision is made for a single ring.

The invention will in any case be clearly understood by consideration of the following description, reference being made to the accompanying drawings which are given solely by way of non-limitative example.

In the drawing:

FIGURE l is a central longitudinal sectional View of a cylinder constructed in accordance with the invention.

FIGURE 2a is a sectional View taken along the line II-II of FIGURE l showing the position of the parts in the nonexpanded condition of the liner.

FIGURE 2b is a View similar to FIGURE 2a, showing the condition of the parts in the expanded condition of the mer.

As can be seen from FIGURE l, the cylinder essentially consists of a hollow shaft 1 -on which is mounted a series of antifriction bearings 2, a series of female rings 3 and a series of male rings 4.

Except for the end bearings, each antifriction bearing 2 is engaged on its opposite axial sides by two female rings 3 which are fitted without play over the hollow cylinder shaft. On the other hand, the male rings 4 which are positioned between the female rings are mounted on the hollow shaft with a certain play. Moreover, it will be clearly seen from the circle 5 which is shown in broken lines that the useful faces of the different rings are portions of spheres which are centered on the axis of the cylinder.

One of the end antifriction bearings is engaged at its outer axial side by a nut o which is screwed on the cylinder shaft, there being in turn screwed in said nut a locking end-piece 7 which is integral with the shaft-journal 8, said shaft-journal being engaged in the journal-bearing 9.

Provision is also made at the opposite end of the cylinder shaft for an outer nut 10 which is adapted to lock the rings and antifriction bearings against the nut 6 and which is integral with the shaft-journal 11, said shaftjournal being engaged in the journal-bearing 9.

It will be noted that the shaft-journal 11 is fitted with a ring 12 to which is secured a lever 13 which can be operated either manually or automatically so as to adjust the angular keying of the cylinder by rotational displacement. It will be apparent that this angular keying is important if the cylinder is employed with a certain curvature since said curvature must be located in a welldetermined plane.

Similarly, it will be noted that the journal-bearings 9 and 9' have spherical bearing surfaces which thus permits the variable camber of the cylinder in .a manner which is well known.

A tube 16 is supported on the antifriction bearings and also on two end-rings 14 and 15, there being fitted over said tube a rubberized sheath 17, the combined assembly thus forming the cylinder bushing which is terminated at its ends by locking rings 18 through which can pass a series of clamping screws 19 which cooperate with the tube 16 and with the end rings 14 and 15.

It will further be noted that the cylinder shaft is provided with holes 20 respectively aligned with the rings 4. Ribs 21 extend through the holes 20 and the thickness of the ribs is slightly greater than the thickness of the shaft. The ribs 21 are arranged in an axial line along the shaft 1.

An expandable cylindrical liner tube 22, which can be made for example of rubber, extends within the interior of the cylinder shaft and is closed at the ends thereof by being gripped between an inner conical ring 23 and an outer conical ring 24, said rings being drawn towards each other by a nut 25 threaded onto an extension of ring 23. At one of the cylinder, the shaft-journal 11 is hollow and is adapted to accommodate a rod 26 which is provided with an external thread so as to cooperate with an internal thread of the shaft-journal 11 and which terminates at the outer extremity with a head 27 so as to permit said rod to be turned either manually or automatically. It will be noticed that the end of the rod 26 is adapted to act against the outer end of the adjacent sealing means 23, 24 and 25 for effecting axial movement thereof. The conical rings 23 and 24 at the rightward end of the shaft (FIGURE l) are slidable axially within the shaft 1 so that when the rod 26 is moved leftwardly, said rings 23 and 24 will move in unison with respect to the shaft toward the corresponding rings at the leftward end of the shaft.

It can readily be visualized that, if the liner tube 22 is made leak-tight at both ends and filled with water, any axial movement of the rings 23 and 24 leftwardly in FIGURE l will cause said liner tube to expand While rightward movement will permit said liner tube to contract radially, or in other words will tend either to reduce or increase the available volume or water capacity of said tube. When the rightward end of the liner tube is moved toward the leftward end, the liner tube expands radially and thrusts the ribs 21 outwards whereas reverse movement permits the reverse movement of the ribs to take place in response to relieving the pressure on the water. In the irst case, the ribs 21 move the rings 4 radially outwardly; in the second case, the reverse movement takes place.

If the rings 4 move radially outwardly, it is necessary to ensure that the distance between the portions of the two rings 3 closest to said ribs increases; conversely, this distance can decrease on the opposite radial side of the shaft. In order to achieve this result, the rings 3 must therefore carry out movements of rotation about their central point. Since the said rings 3 are fitted without play over the cylinder shaft, the aforesaid movements of rotation are accompanied by a bending movement of the cylinder shaft, the amplitude of which depends on the movement of the rings 4 and therefore on the intensity of the action exerted on the head 27.

It will be readily apparent that the said bending movement is transmitted by the antifriction bearings to the bushing, and it will be understood that a curvature which can be varied to a more or less substantial extent can accordingly be imparted to the cylinder as hereinabove described, thereby permitting the possibility of utilizing said cylinder either as a curved cylinder or as a prestressed conventional cylinder in the event that the forces which are liable to be exerted on said cylinder during operation may tend to impart a reverse curvature to said cylinder.

It will in any case be understood that the embodiment of the invention which has just been described has been given solely by Way of non-limitative example and that a large number of detail modications can be made therein without consequently departing either from the scope or the spirit of the invention.

In particular, it is self-evident that the controlling actions produced by means of the lever 13 or the head 27 could be other than manual and could even be made automatic in dependence on a factor such as the deformation to which the material being processed is to be subjected or on the weight of said material.

What I claim is:

1. A variable-camber cylinder, comprising:

an elongated shaft;

bearings mounted on said shaft at axially spaced points therealong;

an outer cylinder mounted on said bearings surrounding and spaced radially outwardly from said shaft;

a plurality of relatively radially movable bearing elements mounted on said shaft between adjacent bearings, the adjacent axial end faces of a pair of adjacent relatively radially movable bearing elements being of cooperating partially spherical shape, one of said pair of bearing elements being mounted for radial movement with respect to said shaft and the other bearing element of said pair being fixed with respect to the adjacent bearing against radial movement with respect to said shaft; and

means for moving said radially movable bearing elements radially with respect to said shaft for imparting to said shaft a curvature which is transmitted t0 said cylinder by said bearings.

2. A variable-camber cylinder according to claim 1, in which at least three axially spaced-apart bearings are mounted on said shaft and cooperating pairs of relatively radially movable bearing elements are provided between each pair of adjacent bearings, said shaft is hollow and said means for moving said radially movable bearing elements comprises an expandable liner tube which extends longitudinally within the interior of said shaft, ribs engaging said liner tube and projecting through openings in said elongated shaft into contact with said radially movable bearing elements whereby when said liner tube is expanded, said ribs are moved radially outwardly to effect radial outward movement of said radially movable bearing elements.

3. A variable-camber cylinder according to claim 2, in which said liner tube is hollow and is iilled with a liquid, and including axially movable means mounted on one end of said shaft and engageable with one end of said liner tube for effecting expansion thereof.

4. A variable-camber cylinder according to claim 1, in which the bearing elements between each pair of adjacent bearings consists of two female rings Whose partially spherical faces have a common axis of curvature and a male ring interposed between said female rings and having its opposite axial end faces curved about the same axis as the spherical faces of said female rings.

5. A variable-camber cylinder according to claim 4, in which the female rings are xed against radial movement with respect to said shaft and said male ring is mounted for radial movement with respect to said shaft.

6. A variable-camber cylinder as defined in claim 5, in which the female rings are secured to opposite sides of each antifriction bearing and including end bearings on the opposite axial ends of said shaft, said end bearings each having a single female ring associated therewith.

References Cited by the Examiner UNITED STATES PATENTS 1,314,342 8/1919 Lawrence 29-113 2,648,122 8/ 1953 Hornbostel 29-113 2,898,662 8/ 1959 Robertson 26-63 3,070,872 1/ 1963 Ulrichs et al. 29-113 3,098,284 7/1963 Hornbostel 29-113 FOREIGN PATENTS 893,426 4/ 1962 Great Britain.

WALTER A. SCHEEL, Primary Examiner. 

1. A VARIABLE-CAMBLER CYLINDER, COMPRISING: AN ELONGATED SHAFT; BEARINGS MOUNTED ON SAID SHAFT AT AXIALLY SPACED POINTS THEREALONG; AN OUTER CYLINDER MOUNTED ON SAID BEARINGS SURROUNDING AND SPACED RADIALLY OUTWARDLY FROM SAID SHAFTF; A PLURALITY OF RELATIVELY RADIALLY MOVABLE BEARING ELEMENTS MOUNTED ON SAID SHAFT BETWEEN ADJACENT BEARINGS, THE ADJACENT AXIAL END FACES OF A PAIR OF ADJACENT RELATIVELY RADIALLY MOVABLE BEARING ELEMENTS BEING OF COOPERATING PARTIALLY SPHERICAL SHAPE, ONE OF SAID PAIR OF BEARING ELEMENTS BEING MOUNTED FOR RADIAL MOVEMENT WITH REPECT TO SAID SHAFT AND THE OTHER BEING ELEMENT OF SAID PAIR BEING FIXED WITH RESPECT TO THE ADJACENT BEARING AGAINST RADIAL MOVEMENT WITH RESPECT TO SAID SHAFT; AND MEANS FOR MOVING SAID RADIALLY MOVABLE BEARING ELEMENTS RADIALLY WITH RESPECT TO SAID SHAFT FOR IMPARTING TO SAID SHAFT A CURVATURE WHICH IS TRANSMITTED TO SAID CYLINDER BY SAID BEARINGS. 